The functions of a computer-assisted surgery (CAS) system may include pre-operative planning of a procedure, presenting pre-operative diagnostic information and images in useful formats, presenting status information about a procedure as it takes place, and enhancing performance. The CAS system may be used for procedures in traditional operating rooms, interventional radiology suites, mobile operating rooms or outpatient clinics.
Navigation systems may be used to display the positions of surgical tools with respect to preoperative or intraoperative image datasets. These images may include two-dimensional fluoroscopic images, and three-dimensional images generated using, for example, magnetic resonance imaging (MRI), computed tomography (CT) and positron emission tomography (PET). Some navigation systems make use of a tracking or localizing system. These systems locate markers attached or fixed to an object, such as an instrument or a patient, and track the position of markers. These tracking systems may be optical and/or magnetic, but may also include acoustic and/or ultrasonic systems. Optical systems may have a stationary stereo camera pair that observes passive reflective markers or active infrared LEDs attached to the tracked tools. Magnetic systems may have a stationary field generator that emits a magnetic field that is sensed by small coils integrated into the tracked tools.
Most navigation systems transmit information to the surgeon via a computer monitor. Conversely, the surgeon transmits information to the system via a keyboard and mouse, touchscreen, voice commands, control pendant, or foot pedals, and also by moving the tracked tool. The visual displays of navigation systems may display multiple slices through three-dimensional diagnostic image datasets.
Autonomous robots have been applied commercially to joint replacement procedures. These systems make precise bone resections, improving implant fit and placement relative to techniques that rely on manual instruments. Robots may also utilized haptic feedback systems to provide for semi-autonomous control, as described in greater detail below. Registration is performed by having the robot touch fiducial markers screwed into the bones or a series of points on the bone surfaces. Cutting is performed autonomously with a high-speed bur, although the surgeon can monitor progress and interrupt it if necessary. Bones may be clamped in place during registration and cutting, and are monitored for motion, which then requires re-registration.
Despite the advances in robotic devices and methods to perform or assist in the performance of certain surgeries, further advances are still desirable. For example, while robotic systems have been used to resect a patient's bone, it would be desirable to integrate the same robot into related procedures, such as in creating and/or applying a bone graft.